Recommend me an oil. 2017 WRX STI.

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Greetings,

I've been researching like a mad man on what to put in the car when the factory fill has to be replaced which leads me to ask two questions in this post (more on that at the end). Even after reading all this information, I've been some somewhat overwhelmed with choices available thus the reason I am seeking your advice with something more tailored to the way I drive.


The other question is in regards to the factory fill, I was planning on replacing it at 1,000 miles, but after reading some, I gathered that the FF has what the engine needs more of during the break in process. Is there any truth to this? I now have 1,100 miles on it.


My concern is that I really want to stay warranty compliant, so that leaves some oils out of the picture that are known to be less prone to shearing in this vehicle. Here are a few of the oils I was considered using based on my findings.



Pennzoil Ultra Platinum PurePlus made from NG 5w-30

Castrol Edge/SPT 5w-30 ?

Amsoil offerings OE,XL,& SS 5w-30

and of course the Subaru Synthetic 5w-30






1. What kind of vehicle you have

2017 WRX STI


2. What your owner's manual says -- not just viscosity, but certifications (look for acronyms like API SM, ILSAC GF-4, etc.) and change intervals as well

5w-30 API SN with the words resource conserving/ILSAC GF-5



3. Where you live

Florida



4. How you drive (easy? hard? fast? slow?)

Will be driving it easy for the most part with the occasional spirited drive. Car most likely wont see a track in the foreseeable future.




5. What your daily drive is like (short trips? long trips? city? highway?)

It's my daily driver, 28 mile commute one way, 23 of which is all highway, the rest city driving. Also the occasional weekend drive.




6. Whether your car has any known problems

Spun bearings, broken ring lands from what the internet tells me.



















Thanks for any help
 
Rotella T6 is very popular for that engine series.

You will be compliant with a 5w40 as your manual specifies other grades are ok for severe use.

I'd change frequently every 4000 miles or so.. more often with track use.
 
FF Subaru is Motul
MOTUL%20SUBARU%20BY%20MOTUL%20C2%205W-30%205L.jpg
 
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Yeah, if you want to stay strict about warranty compliancy, some of the NASIOC STI favorites like T6 5W40 and M1 5W30 ESP are questionable choices at best.
The PQIA said that Amsoil SS 5W30 is not API licensed, but it did meet SN and ILSAC GF-5 standards by their analysis. Amsoil OE 5W30 is API SN and ILSAC GF-5, not sure about XL. I looked around for information about the Subaru synthetic 5W30 and never found anything worthwhile...obviously no warranty issue with that! Given that Amsoil OE 5W30 was pretty much a dead ringer for Mobil Super Synthetic by the PQIA's testing and that I have heard that Castrol was reformulated and I haven't seen a recent VOA, Pennzoil would probably be my choice off your list.

FYI...the Pennzoil results are definitely obsolete due to the newer GTL products and I think the Castrol is old, too.
http://www.pqiamerica.com/March2013PCMO/Marchsyntheticsallfinal.html

Also FWIW, here is a more recent Pennzoil Platinum 5W30 analysis...IDK if the Ultra version would add Boron??
http://www.pqiamerica.com/June 2014/pennzplatinum.htm
 
I'd go with a fully synthetic 0w40 or 5w40. Most of those are on the thin side of 40. I've seen plenty of UOA here where the 30 grade oils thin out to 20. I have also owned a wrx in the past and run 40 grade oils.

I think the manual calls for 30 grade to meet their fuel efficency claims. It will save three poofteenths of a mpg.
 
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I like 40 grade oils in WRX's, like Edge or M1 0W-40.

However if you want a API SN 5W-30, then consider M1 5W-30 High Mileage. It is a name brand full synthetic, and has just been reformulated to be API SN (previously a high zinc SL oil).

A regular ILSAC 5W-30 has HTHS of 3.0 +/- 0.1, but the M1 5W30 HM has a HTHS of 3.3 so it's a much stronger oil and now API SN to meet the requirements of your owners manual (OM). I believe the OM says SN or GF-5, but yours may be worded different.
 
Originally Posted By: SR5
I like 40 grade oils in WRX's, like Edge or M1 0W-40.

However if you want a API SN 5W-30, then consider M1 5W-30 High Mileage. It is a name brand full synthetic, and has just been reformulated to be API SN (previously a high zinc SL oil).


A regular ILSAC 5W-30 has HTHS of 3.0 +/- 0.1, but the M1 5W30 HM has a HTHS of 3.3 so it's a much stronger oil and now API SN to meet the requirements of your owners manual (OM). I believe the OM says SN or GF-5, but yours may be worded different.


Interesting...I looked at the PDS online for the US and it still says SL. I will take a peek next time I am in WalMart and see what the bottles there say...with that HTHS, it might be a budget alternative to ESP if it meets some of my other "needs" (low Ca and NOACK, dose of moly).
 
Tiir, I can appreciate your desire to buy "the best" motor oil for your new STI. However, if you are tempted to use an oil weight or a product that does not conform to Subaru's very specific engine oil requirements for the STI, you really should take the time to read all of the treads on NASIOC regarding warranty issues and the problems that Subaru owners have encountered over many years when they were unable to demonstrate conclusively that they had used a motor oil, and specifically the weight oil, specified by the company.
 
Amsoil XL 10w/30 looks good on paper, and is API certified. The 10w/30 has a NOACK of 5.7% and a HTHS of 3.3 and for 6 bucks a quart with PC pricing, not a bad deal. If your looking to stay warranty compliant and stick with a 30 weight you can always buy your 5 quarts of 30 weight for correct documentation and sub one qt or so for a 40 weight and no one would ever know.

If you research the STI when it comes to oil many choose to use a 40wt as the EJ tends to be a bit hard on oil.

Finding a good 30 weight that won't shear so easily and not cost to much would be ideal. Would probably be fine with 5k OCI's
 
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The factory fill Idemitsu is higher in ZDDP and moly than the dealer service fill. I would run it to at least 3k miles (even though it's a 20 grade by the time you get the car home). IMO, the Subaru branded dealer service Idemitsu oil is nothing special and you'd do just as well on any GF-5 5W-30 from Wallly World. As noted Amsoil SS is not GF-5. I would also follow the severe service oil change interval of 3,000 miles because there will be some oil shearing going on.

Because you have an EJ, there's no concern about needing to use a low SAPS ACEA C3 5W30 like a lot of WRX guys are doing. That said, these oils are thicker at operating temp and have a higher High Temp High Shear than GF5 oils which means happier bearings.

FWIW, the owner's manual still states that thicker viscosity is required in high temps and 5W40 is probably still shown on the temp chart. Personally I wouldn't run a GF5 5W30 in an STI. And if you do ANY mods (including just a reflash) then absolutely do not run GF5.

Edit: Owner's manual details I mentioned are on page 12-5 (thicker viscosity required in hot weather and 5W40 on the temp chart).

http://techinfo.subaru.com/proxy/126125/pdf/ownerManual/126125_2017_WRX/MSA5M1705ABSTIS_17.pdf
 
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Originally Posted By: bluesubie
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The factory fill Idemitsu is higher in ZDDP and moly than the dealer service fill. I would run it to at least 3k miles (even though it's a 20 grade by the time you get the car home). IMO, the Subaru branded dealer service Idemitsu oil is nothing special and you'd do just as well on any GF-5 5W-30 from Wallly World. As noted Amsoil SS is not GF-5. I would also follow the severe service oil change interval of 3,000 miles because there will be some oil shearing going on.

Because you have an EJ, there's no concern about needing to use a low SAPS ACEA C3 5W30 like a lot of WRX guys are doing. That said, these oils are thicker at operating temp and have a higher High Temp High Shear than GF5 oils which means happier bearings.

FWIW, the owner's manual still states that thicker viscosity is required in high temps and 5W40 is probably still shown on the temp chart. Personally I wouldn't run a GF5 5W30 in an STI. And if you do ANY mods (including just a reflash) then absolutely do not run GF5.

Edit: Owner's manual details I mentioned are on page 12-5 (thicker viscosity required in hot weather and 5W40 on the temp chart).

http://techinfo.subaru.com/proxy/126125/pdf/ownerManual/126125_2017_WRX/MSA5M1705ABSTIS_17.pdf

According owner's manual:
5W-30 synthetic oil is the required oil for optimum engine performance and protection. Conventional oil may be
used if synthetic oil is unavailable


Mobil 1™ 5W-30
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Apologies for the late reply, I really appreciate the responses.


I believe we can all agree that we want what's best for our vehicles. In my case this particular one has made me over zealous, I mean come on, after all, I am posting on a oil forum asking for advice on something I did not even worry about before. Although, I have been lusting over a STI for over a decade, around 14 years actually, so maybe that explains overthinking things.

That being said, I am aware that Rotella T6 along with some other brands of oil that are not really up to par with OEM specs are VERY popular among the WRX/STI community with UOA's to show it. But as far as I am concerned, I am not comfortable running a diesel oil in a gasoline or 0w-40 oils especially under warranty. Believe me when I say this, my intent is not to start a argument about it, I am personally just not willing to risk it.

Out of curiosity I looked up a 2014 WRX STI OM more so before the body refresh. A API-SM 10w-30, 10w-40 & 5w-40 oil is spec'ed for replenishment if needed. In 2015 it changed to what it is now which is interesting for a engine that's been pretty much unchanged over the last decade. I guess in the end we will never really know why the manufacture changes stuff. After reading several threads regarding oil brands, and types along with looking at countless UOA's, I have concluded that if something is going to fail engine wise, it's going to happen regardless of what oil is used.
 
I saw a thread here on the forums where a high powered car that was modified, had used 30 grade as required by the manual but it simply could not cope with the engine and Pennzoil themselves basically told the owner to run a thicker oil. The general theme of the thread was that there is no replacement for viscosity when you are high powered. Not to start a thin vs thick war or anything but Subaru is purely running their 5W30 just to meet fuel economy and emissions [censored]. There is no way that a resource conserving oil is going to protect better than something that is ACEA approved, specifically A3/B4, BMW LL01, MB229.5.

If you want to really be sticking to the books but want something thicker, there are possibilities though. Run a 5W30 A3/B4 BMW LL01 MB229.5 Porsche A40 oil. It will be at the limits of 5W30 and almost in the 40's but it still counts and there's no way Subaru will be able to say that a GF5 is somehow superior to a bunch of Euro specs that are designed to protect high powered euro cars.

Let me sum it up, the Euro spec oils are used in things like BMW, Ferrari, Porsche etc. Can you or anyone come up with some reason it would protect those gasoline engines perfectly for long miles but cause your Subaru to explode?

Also wrong about Rotella. It is not a diesel engine oil only. It is a heavy duty engine oil. It is dual rated for both petrol and diesel making it super popular as you basically can use it on all cars instead of buying tons of different oils. I also used it with fine results in my WRX.

BTW - not having a go at you so please don't feel offended.
 
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Originally Posted By: Hounds
Tiir, I can appreciate your desire to buy "the best" motor oil for your new STI. However, if you are tempted to use an oil weight or a product that does not conform to Subaru's very specific engine oil requirements for the STI, you really should take the time to read all of the treads on NASIOC regarding warranty issues and the problems that Subaru owners have encountered over many years when they were unable to demonstrate conclusively that they had used a motor oil, and specifically the weight oil, specified by the company.


+ one Brazilian.

If you want a bit more viscosity and to stay in the 5w30 grade, you can use Redline 5w30. This will keep you at Factory Spec and not give Subaru any cause to deny a warranty claim.

Will this car be modified or not?
 
Originally Posted By: fredrik94087
Originally Posted By: Hounds
Tiir, I can appreciate your desire to buy "the best" motor oil for your new STI. However, if you are tempted to use an oil weight or a product that does not conform to Subaru's very specific engine oil requirements for the STI, you really should take the time to read all of the treads on NASIOC regarding warranty issues and the problems that Subaru owners have encountered over many years when they were unable to demonstrate conclusively that they had used a motor oil, and specifically the weight oil, specified by the company.


+ one Brazilian.

If you want a bit more viscosity and to stay in the 5w30 grade, you can use Redline 5w30. This will keep you at Factory Spec and not give Subaru any cause to deny a warranty claim.

Will this car be modified or not?

Red Line does not have any API or ILSAC certification.
 
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